In vitro thrombus formation and in vivo hemostasis mediated by platelets irradiated with bactericidal ultraviolet C from xenon flash under flow conditions.

BACKGROUND: We previously reported a flow path-ultraviolet C (UVC) irradiation system for platelet concentrates (PCs) with platelet additive solution (PAS) to minimize contamination by bacteria. Here, we investigated functionalities of irradiated platelets (PLTs) in in vitro thrombus formation and in vivo hemostasis. STUDY DESIGN AND METHODS: PAS-PCs were irradiated with flash UVC using the flow path system. Their variables (PLT count, mean platelet volume, pH, glucose, lactate, glycoprotein [GP] Ib, and activated integrin αIIbß3) were evaluated. Static adhesion to collagen or fibrinogen was analyzed using fluorescent microscopy. Thrombus formation under flow conditions was assessed using a collagen-coated bead column. Adenosine diphosphate (ADP)-induced Akt phosphorylation was determined by western blot. In vivo hemostasis and circulatory survival of PLTs were assessed with a rabbit bleeding model. RESULTS: All variables, except for GPIb expression, were slightly, but significantly, impaired after flash UVC irradiation throughout the 6-day storage period. No difference was observed in static adhesion to either collagen or fibrinogen between irradiated and nonirradiated PAS-PCs. In vitro thrombus formation of flash UVC-irradiated PAS-PCs was significantly greater than that of nonirradiated PAS-PCs. ADP-induced Akt phosphorylation was enhanced in irradiated PAS-PCs. In vivo hemostatic efficacy was comparable between the groups on Day 1. The efficacy declined in nonirradiated PAS-PCs on Day 5, while it was retained in flash UVC-irradiated PAS-PCs. Circulatory survival of PLTs was lower in irradiated PAS-PCs. CONCLUSIONS: PAS-PCs irradiated with UVC from xenon flash have favorable properties to achieve hemostasis compared with nonirradiated PAS-PCs.

Thermal coagulum formation and hemostasis during repeated multipulse Nd:YAG laser treatment of cutaneous vascular lesions: animal experiment study.

Laser therapy has been widely used to treat port-wine stain (PWS) and other cutaneous vascular lesions via selective photothermolysis. High incident laser fluence is always prohibited in clinic to prevent the thermal damage in normal skin tissue, leading to insufficient energy deposition on the target blood vessel and incomplete clearance of PWS lesion. In this study, repeated multipulse laser (RMPL) irradiation was proposed to induce acute thermal damage to target blood vessels with low incident fluence (40 J/cm2 for 1064-nm Nd:YAG laser). The feasibility of the method was investigated using animal models. Repeated multipulse irradiation cycles with 10-min intervals were performed in RMPL. A hamster dorsal skin chamber model with a visualization system was constructed to investigate the instant generation of thermal coagulum and relevant hemostasis by thrombus formation during and after irradiation under 1064 nm Nd:YAG single multipulse laser (SMPL) and RMPL irradiation. The diameter of the target blood vessel and the size of thermal coagula were measured before and after laser irradiation. The reflectance spectra of the dorsal skin were measured by a reflectance spectrometer during RMPL. Stasis thermal coagula that clogged the vessel lumen were generated during SMPL irradiation with low incident fluence. However, there was no acute thermal damage of blood vessels. Reflectance spectra measurement showed that the generation of thermal coagula and subsequent thrombus formation increases blood absorption by more than 10% within the first 10 min after laser irradiation. Acute vessel thermal damage could be induced in the target blood vessel by RMPL with low incident fluence of 40 J/cm2. Compared with our previous SMPL study, nearly 30% reduction in incident laser fluence was achieved by RMPL. Low fluence RMPL may be a promising approach to improve the therapeutic outcome for patients with cutaneous vascular lesions by improving energy deposition on the target blood vessel.

Cryopreservation of UVC pathogen-inactivated platelets.

BACKGROUND: Extending the platelet (PLT) shelf life and enhancing product safety may be achieved by combining cryopreservation and pathogen inactivation (PI). Although studied individually, limited investigations into combining these treatments has been performed. The aim of this study was to investigate the effect of PI treating PLTs before cryopreservation on in vitro PLT quality and function. STUDY DESIGN AND METHODS: ABO-matched buffy coat-derived PLTs in PLT additive solution (SSP+; Macopharma) were pooled and split to form matched pairs (n = 8). One unit remained untreated and the other was treated with the THERAFLEX UV-Platelets System (UVC; Macopharma). For cryopreservation, 5% to 6% dimethyl sulfoxide was added to the PLTs, and they were frozen at -80°C. After being thawed, untreated cryopreserved PLTs (CPPs) and UVC-treated CPPs (UVC-CPPs) were resuspended in plasma. In vitro quality was assessed immediately after thawing and after 24 hours of room temperature storage. RESULTS: UVC-CPPs had lower in vitro recovery compared to CPPs. By flow cytometry, PLTs demonstrated a similar abundance of GPIX (CD42a), GPIIb (CD41a), and GPIbα (CD42b-HIP1), while the activation of GPIIb/IIIa (PAC-1) was increased in UVC-CPPs compared to CPPs. UVC-CPPs demonstrated greater phosphatidylserine exposure (annexin V) and microparticle shedding but similar P-selectin (CD62P) abundance compared to CPPs. UVC-CPPs displayed similar functionality to CPPs when assessed using aggregometry, thromboelastography, and thrombin generation. CONCLUSIONS: This study demonstrates the feasibility of cryopreserving UVC-PI-treated PLT products. UVC-PI treatment may increase the susceptibility of PLTs to damage caused during cryopreservation, but this is more pronounced during postthaw storage at room temperature.

The relationship of systemic markers of haemostasis with retinal blood vessel responses in cardiovascular disease and/or diabetes.

Background Hypercoagulability is a leading factor in diabetes and cardiovascular disease. Retinal vessel responses to flickering light are an important tool for assessing ocular function. We hypothesised a significant relationship between systemic markers of haemostasis and retinal vessel function. Methods Intra-ocular pressure and retinal microcirculation function were measured in 116 patients with diabetes and/or cardiovascular disease using unstimulated and stimulated arterial and venous retinal vessel responses to flickering light. Haemostasis was evaluated by platelet microparticles, soluble P selectin, and five functional markers of fibrin clot formation and lysis, hyperglycaemia by HbA1c. Results Intra-ocular pressure was linked to the rates of clot formation (p = 0.006) and clot dissolution (p = 0.013) whilst central retinal vein equivalent was linked to HbA1c (p = 0.017). In the first of three flickering light cycles only, arterial baseline diameter fluctuation was linked to the lag time to clot formation (p = 0.017), whilst maximum venous dilatation was linked to HbA1c (p = 0.001) and clot density (p = 0.011). HbA1c was linked to venous dilatation amplitude (p = 0.003). There were no significant links between any ocular index and any platelet index. Conclusions In addition to glycaemia, several haemostasis measures, but no measures of platelet activity, are linked to ocular and retinal blood vessel indices in patients with diabetes and/or cardiovascular disease. These associations may have pathophysiological significance.

Plasma treated with amotosalen and ultraviolet A light retains activity for hemostasis after 5 days post-thaw storage at 1 to 6o C.

BACKGROUND: Plasma thawed and stored at 1 to 6° C for up to 5 days (thawed plasma [TP]) provides rapid availability in emergencies and reduces plasma waste, but it carries risks of coagulation factor loss or activation, bacterial outgrowth, and viral contamination. We characterized changes in amotosalen/ultraviolet A (UVA) light pathogen-reduced, fresh-frozen plasma (FFP) and plasma frozen within 24 hours (PF24) with post-thaw storage. STUDY DESIGN AND METHODS: Amotosalen/UVA light-treated FFP and PF24 were thawed after approximately 3 to more than 12 months of frozen storage and held at 1 to 6° C for 5 days. Global assessments of coagulation and hemostatic, antithrombotic, and activation markers indicative of function were assessed. RESULTS: Day 5, thawed amotosalen/UVA light-treated FFP and PF24 contained levels of Factors II, V, VIII, IX, X, von Willebrand factor ristocetin cofactor (vWF:RCo), fibrinogen, antithrombin III (ATIII), protein C, and protein S similar to the levels measured in Day 5 TP, as described in the Circular of Information. Thrombin generation was robust on Day 5 (amotosalen/UVA: FFP = 1866 ± 402 nM/minute; PF24 = 1800 ± 277 nM/minute). Most factor activities on Day 5, including von Willebrand factor-cleaving protease (ADAMTS-13), were more than 90% of Day 0 values, except for known labile Factors V and VIII and protein S. All units contained greater than 0.4 IU/mL protein S and α2 plasmin inhibitor on Day 5. Global functional indices, including thrombin-antithrombin complexes, nonactivated thromboplastin time, and thrombin-generation peak height, did not indicate activation of the coagulation cascade, although isolated units showed raised levels of Factor VIIa and Complement 3a. CONCLUSION: Amotosalen/UVA light-treated FFP and PF24 demonstrated retention of procoagulant and antithrombotic activity after 5 days post-thaw storage at 1 to 6° C.

Human platelet concentrates treated with microbicidal 405 nm light retain hemostasis activity.

Chemical and UV light-based pathogen reduction technologies are currently in use for human platelet concentrates (PCs) to enhance safety from transfusion-transmitted infections. Relative to UV light, 405 nm violet-blue light in the visible spectrum is known to be less harmful. Hence, in this report for the first time, we have assessed the global hemostasis activity of PCs stored in plasma and the activities of six plasma coagulation factors (CFs) as a measure of in vitro hemostatic activity following exposure to the microbicidal 405 nm light. Apheresis PC samples collected from each screened human donor (n = 22) were used for testing of PCs and platelet poor plasma (PPP). Both PCs and PPPs were treated for 5 h with 405 nm light to achieve a previously established microbicidal light dose of 270 J/cm2. Activated partial thromboplastin time and prothrombin time-based potency assays using a coagulation analyzer and hemostatic capacity via Thromboelastography were analyzed. Thromboelastography analysis of the light-treated PCs and plasma present in the PCs showed little difference between the treated and untreated samples. Further, plasma present in the PCs during the light treatment demonstrated a better stability in potency assays for several coagulation factors compared to the plasma alone prepared from PCs first and subjected to the light treatment separately. Overall, PCs stored in plasma treated with 405 nm violet-blue light retain activity for hemostasis.

Hemostatic system in Wistar rats in different types of oxidative stress.

We studied parameters of hemostatic homeostasis in isolated and combined exposure to low-intensity γ-irradiation in a low dose, hyperbaric oxygenation, and antiorthostatic hypokinesia. Complex effects of the above stress factors are accompanied by a pronounced hypercoagulable shift with signs of thrombinemia against the background of depressed fibrinolysis, which indicates the risk of intravascular blood coagulation.

Don't be a clot: a radiologist's guide to haemostasis including novel antiplatelet and anticoagulant therapies.

Normal haemostasis relies on the complex interactions of the coagulation cascade, platelets, and the endothelium. In this review, the roles of each of these elements are described as well as common causes for their derangement. Haemostasis may be manipulated via pharmacological means and in recent years there has been a significant increase in the number of agents available for influencing haemostatic mechanisms. It is essential that radiologists are aware of these mechanisms and drugs if they are to perform image-guided procedures safely. In addition to describing the relevant pathways and drugs, practical tips are provided.

Early response of mechanically exposed dental pulps of swine to antibacterial-hemostatic agents or diode laser irradiation.

OBJECTIVES: The purpose of this study was to compare the effectiveness of an antibacterial and hemostatic agent to diode laser irradiation in the healing of mechanically exposed porcine pulps. MATERIALS AND METHOD: The experiment required three adult swine (Sus scrofa domestica, Yorkshire) with 36 teeth prepared with occlusal penetrations into the pulpal tissues. The preparations were performed under general anesthesia and the pulps were exposed using high speed instrumentation with rubber dam isolation and a disinfected field. Following instrumentation the coronal pulpal tissue was amputated and immediately treated with ferric sulfate and chlorhexidine semi-gel (12), diluted Buckley' formocresol solution (12) for 5 minutes or laser irradiation with a diode laser (12). After treatment, hemostasis was obtained and a ZOE base applied to the treated pulps (36). The pulpal bases were all covered with a RMGI (Fuji II LC). The tissue samples were collected at 4 weeks (28 days). Following fixation, the samples were de-mineralized, sectioned, stained and histologically graded with a scale of 0-4. RESULTS: The treatment groups were statistically different with the Laser Treated Group demonstrating the least inflammation. CONCLUSION: Pulpotomy treatment with the KaVo Gentle Ray Diode Laser demonstrated significantly less inflammation than the other two pulpal therapy modalities. The ferric sulfate and chlorhexidine mixture demonstrated the greatest inflammation as histologically graded. Also, the histological sections of pulpotomized swine teeth treated with the ferric sulfate and chlorhexidine mixture presented with black pigmented areas in the pulp and surrounding tissue. The formocresol group (clinical standard) and the diode laser group did not present with the black precipitate.

Haemostatic radiotherapy for bleeding cancers of the upper gastrointestinal tract.

Bleeding can cause significant morbidity in patients with upper gastrointestinal malignancies. Palliative radiotherapy can palliate bleeding effectively across numerous cancer sites such as the lung and rectum. The data available regarding the role in bleeding from upper gastrointestinal cancers are limited to a single meta-analysis, a phase 2 trial, eleven retrospective cohorts and two case reports, with the majority focusing on gastric cancer. From the data available radiotherapy appears to be a well-tolerated, effective haemostatic agent that should be considered in all patients with bleeding from an upper gastrointestinal malignancy. Questions remain regarding the radiobiology of haemostasis and the optimum fractionation schedule. There is no convincing evidence that protracted higher dose regimens provide additional benefit. Commonly used fractionation schedules use 1, 5 or 10 fractions. Short fractionation schedules have been used in patients with deteriorating performance status.

Dual-wavelength-assisted thermal hemostasis for treatment of benign prostate hyperplasia.

Laser treatment on a large size of prostate gland often encounters significant bleeding that can prolong the entire procedure and cause urinary complications. The current study investigates the feasibility of dual-wavelength (532 and 980 nm) application to achieve rapid hemostasis for 532-nm laser prostatectomy. Porcine kidney and bleeding phantom models were tested to quantify the degree of the irreversible tissue coagulation and to estimate the time for the complete hemostasis, respectively. The ex vivo kidney testing verifies that the dual-wavelength created up to 40% deeper and 25% wider coagulation regions than a single wavelength does. The bleeding phantom testing demonstrates that due to the enhanced thermal effects, the simultaneous irradiation yields the complete photocoagulation (~11 seconds) whereas 532 or 980 nm hardly stops bleeders. Numerical simulations validate that the combined optical-thermal characteristics of both the wavelengths account for the augmented thermal coagulation. The dual-wavelength-assisted coagulation can be a feasible treatment to entail the rapid hemostasis and to facilitate the laser prostatectomy in an effective manner.

Hemostatic function, survival, and membrane glycoprotein changes in young versus old rabbit platelets.

Although in vitro studies have demonstrated functional differences between young and old platelets, in vivo differences have not been precisely established. Therefore the in vivo hemostatic function of young and old platelets and the survival time have been examined in rabbits. The hemostatic function was measured by performing serial ear bleeding times in irradiation-induced thrombocytopenic rabbits. After irradiation with 930 rad the platelet count gradually diminished reaching a nadir ( approximately 20 x 10(3)/mul) at 10 d. The platelets present in the circulation, 7-10 d after irradiation, were considered old platelets, and the platelets present after recovery, 11-14 d postirradiation, young platelets. The measurement of platelet size was consistent with the hypothesis that platelets become smaller with age: the mean size was 3.84 mum(3) for old platelets and 5.86 mum(3) for young platelets. Regression analysis of the relationship between the bleeding time and the platelet count in 18 rabbits showed a significantly different slope for rabbits with predominantly old platelets compared with rabbits with predominantly young platelets (P < 0.001). Young platelets were more effective giving much shorter bleeding times than old platelets at comparable platelet counts. Survival times of young and old platelets were measured using platelets harvested on day 8 postirradiation (old platelets) and day 12 postirradiation (young platelets) that were labeled and then reinjected into normal recipient animals. The mean platelet survival time, calculated by gamma function, of old platelets was 28.8 h; of young platelets, 87.4 h; and of normally circulating heterogeneous platelets, (normal platelets) 53.0 h. Notably, the survival of old platelets was found to be exponential, and of young platelets, linear. Analysis of the membrane glycoproteins in young, old and normal platelets indicated that there was no qualitative difference amongst the young, normal, and old platelets. The relative relationship among all the glycoprotein peaks was equal and the only changes observed were quantitative, with young platelets having significantly more membrane glycoprotein per cell than old platelets and normal platelets. Normal platelets had intermediate concentrations of each glycoprotein. These results demonstrate that young platelets are hemostatically more effective in vivo than old platelets. The data are compatible with the hypothesis that platelets age in the circulation by losing membrane fragments and then after becoming senescent, are removed from the circulation by a random process.

Haemostatic properties of human plasma subjected to a sterilizing dose of gamma irradiation in the presence of ascorbate.

The objective was to study the effects of gamma irradiation, in the presence of sodium ascorbate, on coagulation/fibrinolytic activity of fresh frozen plasma to be applied to inactivate the transfusion-transmitted viruses in plasma-derived products. Plasma was irradiated (50 kGy total dose, on dry ice) using a 60Co source. The plasma proteins were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and western blot and the following parameters estimated: prothrombin time, functional fibrinogen concentration, thrombin-induced fibrinogen polymerization, plasminogen activity, and tissue-type plasminogen activator-induced conversion of plasminogen to plasmin. In irradiated plasma a moderate fragmentation of the most labile plasma proteins was found. The prothrombin time was prolonged (1.5-fold), functional fibrinogen was significantly reduced (60%), fibrinogen polymerization was impaired, plasminogen was predominantly maintained (90%) and tissue-type plasminogen activator-induced conversion of plasminogen to plasmin was unchanged. Ascorbate (25 mmol/l) raised the level of functional fibrinogen in irradiated plasma (to 50%; P=0.0245) and slightly accelerated its polymerization. The small protective effect of ascorbate might be due to inhibition of the radiation-induced fibrinogen oxidation and/or fragmentation but addition of other antioxidants/stabilizers would be crucial when a high irradiation dose, an effective treatment for inactivation of the most resistant viruses, is applied.

In vivo cancer diagnosis with optical spectroscopy and acoustically induced blood stasis using a murine MCa35 model.

Ultrasound-induced blood stasis has been observed for more than 30 years. Most of the literature has been focused on the health risks associated with this phenomenon and methods employed to prevent stasis from occurring during ultrasound imaging. To date, experimental observations have been either in vitro or invasive. The current work demonstrates ultrasound-induced blood stasis in murine normal leg muscle versus tumor-bearing legs, observed through noninvasive measurements of optical spectroscopy, and discusses possible diagnostic uses for this previously undesirable effect of ultrasound. We demonstrate that, using optical spectroscopy, effects of ultrasound can be used to differentiate tumor from normal leg muscle tissue in mice. Finally, we propose a novel diagnostic algorithm that quantitatively differentiates tumor from nontumor with maximum specificity 0.83, maximum sensitivity 0.79, and area under receiver-operating-characteristics curve 0.90.

[Effect of low-intensity laser radiation on lipid metabolism and hemostasis in patients with myocardial infarction].

Progression of coronary atherosclerosis often causes complications resulting in myocardial infarction, early disability and death of patients with coronary heart disease. Low efficacy of medicines against coronary atherosclerosis progression after myocardial infarction gave rise to investigations of nonpharmacological methods, laser radiation, in particular. Our study shows a noticeable positive effect of low-intensity laser radiation on blood lipid spectrum and hemostasis. This makes laser therapy promising in combined rehabilitation of postmyocardial infarction patients.

Disorder of Endothelia Vessels' Functional State with Malignant Tumors in Patients Exposed Anthropogenic Radiation.

The aim of this research is to determine the characteristics of endothelial factors and the hemostatic system conditions with malignant neoplasms patients, which were exposed to ionizing radiation. Total number of examined people is 223, 153 of them are patients with gastrointestinal tract oncopathology. The article presents the results of the analysis of numerical indicators of endothelial condition and platelet hemostasis of patients, who had cancer. They lived in the regions of Kazakhstan, subjected to contamination of radionuclides as a result of nuclear weapons tests, which took place in this region from 1949 to 1989. These results then were compared to cancer patients and healthy individuals with no radiation risk. The study revealed the presence of higher levels of endothelial dysfunction and following trigger of the hemostatic system in patients with malignant tumors of the gastrointestinal tract. In particular, the defined high degree of endothelial dysfunction include endothelium- dependent vasodilation, content desquamated endothelial cells in peripheral blood and von Willebrand factor. These indicators have a clear correlation with the degree of disorder of studied parameters of the hemostasis, which can cause the development of thrombotic complications.

Blood flow stasis induced by cw-Nd:YAG laser irradiation: comparative morphology of mesenteric and choroidal vessels in pigmented rabbits.

cw-Nd:YAG laser radiation was effective in producing blood flow stasis within arteries (35-40 microns in diameter) of pigmented rabbit mesentery (beam spot size: 80 microns; fluence: 2 x 10(4) J cm-2) and choroid (beam spot size: 200 microns; fluence: 6 x 10(2) J cm-2). However, the mechanism by which this was achieved differed in each case, and depended upon the energy absorbing structures present in the irradiated tissue. In non-pigmented tissue, such as the mesentery, haemoglobin represents the primary absorption centre, and the temperature attained within the vessel lumen (as inferred from morphological changes) is sufficient to denature plasma proteins, in particular fibrinogen, which consequently occlude the vessel lumen and arrest bleeding. In pigmented tissue, such as the choroid, melanocyte granules represent the primary absorption centre, which is thus shifted from the vessel lumen to the stroma. The temperature rise achieved within the vessel lumen is consequently lower, as evidenced by the absence of plasma protein denaturation. Blood flow stasis nonetheless occurs, but is triggered according to the normal haemostatic mechanism.

Effect of high power ultrasound on endothelial cells--an in vitro study of the endothelium--hemostasis interaction.

OBJECTIVE: The goal of this study was to develop an in vitro model system in which the hemostatic effects of high power ultrasound applied to the outer surface of blood vessels during tumor dissection can be simulated and measured. METHODS: Monolayers of endothelial cells (HUVEC, ATCC) in cell culture plates were sonicated with an ultrasound dissector (SONOCA II, Soering) at a frequency of 23.5 kHz. The dissector was equipped with a cooling circuit. The cell cultures were exposed to 2 minutes of continuous ultrasound with intensities of 10, 50, or 100 W/cm(2). To differentiate between heat and sound effects, selected monolayers were warmed for 2 minutes. Finally, the cell cultures were stained with trypan blue to assess for cell death due to membrane disruption. Cytomorphological alterations and changes in the concentration of coagulation parameters in the cell culture medium were evaluated. RESULTS: The cytomorphological alterations were found to depend on ultrasound intensity. They included detachment of single endothelial cells, cell cluster formation and cytoplasmic cavitation. Disruption of the cell membrane integrity was infrequently observed. Of 14 screened coagulation parameters, thromboxane B(2) (TXB(2)), prostaglandin F(1alpha) (PGF(1alpha)), plasminogen activator inhibitor type 1 (PAI-1), thrombomodulin (TM), and thrombospondin (TSP) were found to be ultrasound sensitive. TXB(2) concentrations in the medium increased beginning at low ultrasound intensities (p < 0.01) and were independent of temperature. PGF(1alpha) concentrations peaked at high ultrasound intensities (p < 0.05), and heat alone produced a significant increase in concentration (p < 0.05). At high intensities, the ratio of TXB(2) to PGF(1alpha) shifted in favour of PGF(1alpha). PAI-1 was most strongly secreted at low ultrasound intensities (p < 0.01), and heat resulted in a decrease of concentration (p < 0.05). TM and TSP concentrations correlated strongly and reached a non significant peak at low intensities. CONCLUSION: The results demonstrate that during sonication of endothelial cells in vitro, coagulation parameters are released from distant undamaged cells. HUVEC-cells exhibit a differential hemostaseological response at different ultrasound intensities, and the response is also influenced by heat. Additionally, massive morphological damage can be induced at the endothelium.

[Hemostasis in hens with exposure to low-dose gamma-irradiation in the embryonal period]. / Sistema gemostaza kur pri deistvii malykh doz gamma-oblucheniia v émbrionalnom periode.

Exposure of hen's eggs to irradiation by doses 0.05-1.66 Gy (dose rate 2.56x10-4 Gy/s) in early embryonal period (1st day of incubation of eggs doesn't essentially affect on indices of functional state of haemostasis system of two-month aged individuals, except the activation of contact phase of blood coagulation, in which a hypercoagulation shift within normal fluctuations has been noted.

[Microvascular hemostasis in the phase of postradiation recovery]. / Mikrososudistyi gemostaz v faze postradiatsionnogo vosstanovleniia.

Laser-induced thrombosis was used for studying of thrombogenic properties and thromboresistance of microvessels after total gamma irradiation with a dose of 2 Gy. The increased time of primary haemostasis was stated during postirradiation period. The area of thrombus section was reduced both in the arterioles and the venules after 1 month. But the normalization of this parameter is more intense in the venules.